Fixed bed reactors are used for a variety of reactions, such as various types of hydroprocessing of petroleum feeds. In a typical fixed bed reactor, a liquid feed and a reactive gas, such as hydrogen, are passed through a reactor along the axial direction of the reactor. Optionally, the flow of reactive gas can be counter-current to the flow of liquid along the axial direction.
For catalyzed reactions of gas phase feeds, another type of reactor that can be used is a radial flow reactor. In a radial flow reactor, one or more gases are contacted with a catalyst or adsorbent while flowing in a primarily radial direction. Before and/or after finishing contact with the catalyst or adsorbent, the gases may travel along the axial direction in order to enter or exit the reactor.
U.S. Pat. No. 4,405,562 describes a reactor for performing gas phase catalyzed reactions. A gas is introduced into at least one catalyst bed in a reactor where gasses can enter both axially and radially into the catalyst bed. All of the gas eventually flows in a radial direction in order to exit the catalyst bed, such as via a central exit conduit in the bed.
U.S. Pat. No. 7,829,038 describes a segmented outer catalyst screen for stacked radial flow reactors. A plurality of supports extend out perpendicular from the reactor wall. Screens are attached to adjacent supports to define a catalyst retention area inside the screens and fluid flow channels outside of the screens. An inner central conduit is perforated to allow for distribution of gas into the fluid flow channels.
U.S. Pat. No. 7,271,303 describes a multi-zone process for the production of diesel and aromatic compounds. A hydrocarbonaceous feedstock containing aromatics is hydrocracked to form diesel fuel and xylenes. A naphtha boiling range or lighter side product generated during the hydrocracking can be vaporized and then reformed and/or transalkylated. A radial flow reactor is described as one option for performing the reforming or transalkylation.